The present invention relates to a refrigerator unit and/or a freezer unit comprising a cooling tank as well as an evaporator, preferably a lamellar evaporator, which is accommodated in an evaporator accommodation space in the cooling tank.
In such refrigerator units and/or freezer units comprising an evaporator embedded into the inner tank, said evaporator is seated with a relatively precise fit in the evaporator accommodation space provided therefor. The clicking noises during operation of the unit represent a problem which arises in this context. It can be assumed that these clicking noises are caused by a cyclic freezing of the evaporator to the walls of the evaporator accommodation space and a release of it again due to the regular defrosting process. Since a lot of moisture is present after a defrosting process, residual drops freeze on between the evaporator surface and the inner tank if a cooling takes place again after the defrosting. On a sudden relaxation and an abrupt breaking off of the frozen points, the unwanted clicking noises can occur.
To eliminate, or at least substantially reduce, these clicking noises as a result of the freezing on and releasing again of the evaporator, it has already been proposed to provide a sufficient spacing between the evaporator-module and the rear wall of the unit, whereby a freezing on should be wholly avoided. Such a defined spacing, however, results in a loss of useful inner space.
It is therefore the underlying object of the present invention to provide an improved refrigerator unit and/or freezer unit of the named kind which avoids disadvantages of the prior art and further develops it in an advantageous manner. The clicking noises emitted by the evaporator should in particular be eliminated, or at least substantially reduced, without wasting valuable useful, inner space.
This object is solved in accordance with the invention by a refrigerator unit and/or a freezer unit in accordance with claim 1. Preferred configurations of the invention are the subject of the dependent claims.
It is proposed for the avoidance of the aforesaid clicking noises, starting from the evaporator, to decouple said evaporator from the inner tank of the refrigerator unit and/or freezer unit. In accordance with the invention, the evaporator is provided with a multi-side jacket made from a soft, resilient and/or deformable padding material. A direct freezing together of the evaporator module and of the evaporator environment, in particular of the cooling tank inner wall, is prevented by this jacket. A freezing together of the evaporator and of the padding material, on the one hand, or of the padding material and the inner wall of the unit, on the other hand, can admittedly occur. Relative movements arising due to thermal strains can, however, be balanced by the deformable padding material so that clicking noises arising due to connection which break open suddenly are precluded. Strains and clicking noises no longer occur due to the relative movements which take place in the padding material. The construction space in the interior of the unit is nevertheless used to the best possible degree. No useful space is lost by the jacket of padding material instead of the initially mentioned large, defined air gap. In addition, the jacket can bring about an air seal so that no external air can be directed past the evaporator, which would impair the energy efficiency. The padding material can in particular also have a thermal insulating function and can accordingly act as a thermal insulator, which likewise has a positive effect on the energy consumption.
In a further development of the invention, the jacket is provided at least on the contact sides of the evaporator with which the evaporator comes into contact with walls of the cooling tank, in particular of the evaporator accommodation space. The jacket is therefore provided where the evaporator could freeze on.
It may be optional for specific applications only to provide the jacket on the said contact sides partially, for example, in strip shape. The jacket of insulating material, however, preferably covers the contact surfaces of the evaporator over the whole area. Clicking noises can be largely completely eliminated by a full covering of the contact surfaces of the evaporator by the jacket of padding material. Care is preferably taken in this context that also no open abutting edges remain, but that also the rim regions and edges of the evaporator housing are largely completely sheathed by the insulating material.
Different sides of the evaporator can form the contact surfaces depending on the design of the evaporator. In accordance with a preferred embodiment of the invention, the jacket substantially completely covers two wide sides and three flat sides of the evaporator.
The jacket can generally be made of different materials. In accordance with an advantageous embodiment of the invention, the jacket comprises a foam, in particular a closed-cell polyethylene foam. The jacket is advantageously resiliently deformable at least to a specific degree so that it makes possible the described compensation movements.
In accordance with a particularly advantageous embodiment of the invention, the jacket can be made at least partly hydrophobic, i.e. water repellant, with at least the surface of the jacket in particular being made hydrophobic. The jacket advantageously does not absorb any water during the whole operating period of the unit. This can be achieved, for example, by a jacket made from a closed-cell foam material.
The jacket could generally be made in one piece. The evaporator could, so-to-say, be foamed in at its contact surfaces. The jacket preferably, however, comprises a plurality of foam pieces which are set in an exact fit onto the contact sides or contact areas of the evaporator and terminate flush with one another at their abutment edges so that no open abutment edges of the evaporator remain.
A slight thickness of the jacket of padding material in the range of a few millimeters can already be sufficient. Different wall thicknesses of the jacket can be provided on different sides of the evaporator in accordance with an embodiment of the invention. The jacket can in particular have a larger wall thickness on the side of the evaporator facing the refrigeration space than on the side of the evaporator remote from the cooling space and/or at flat sides of the evaporator. A heat transfer into the freezing space can hereby be suppressed or minimized during defrosting. For example, the jacket can have a thickness of 3 to 5 mm on the side facing the interior space of the refrigerator unit and a thickness of 1 to 3 mm on the other sides of the evaporator. It is, however, understood that, in accordance with another embodiment of the invention, a jacket is used having a uniform, sufficient wall thickness on all sides of the evaporator.
In a further development of the invention, the jacket is connected areally to the respective evaporator surface and is preferably fastened thereto in a force-transmitting manner or in a firmly bonded manner. The jacket made of foam can in particular be adhesively bonded to a sheet metal jacket of the evaporator.
The evaporator can per also already be sufficiently fastened by an exactly fitting insertion into the evaporator accommodation space provided therefor. The evaporator accommodation space is adapted for this purpose with respect to its shape to the outer contour of the evaporator. Provision can preferably be made for the evaporator to be inserted into the evaporator accommodation space with a light press fit which is compensated by a light resilient deformation of the jacket. In this connection, the slightly compressed foam of the jacket holds the evaporator without wobble and secure against impact in the evaporator accommodation space.
Further fastening means can generally be completely dispensed with. To nevertheless prevent a slipping of the evaporator on installation, in accordance with an embodiment of the invention, the evaporator can be fastened to the inner tank using a force-transmitting means, in particular a screw. It has been found to be advantageous for the evaporator to be fastened to the inner container not by plastic plugs or plastic bayonet fittings, but rather by a plurality of screws at different points of the inner tank. This further reduces the formation of clicking noises.
The evaporator accommodation space can generally be of various configurations. In accordance with an embodiment of the invention, it can comprise a substantially tub-shaped recess in the inner wall of the tank which can be closed by an inner cover. The evaporator can be inserted into the evaporator accommodation space in the inner tank from the inner space of the cooling tank. If the inner cover is then placed onto the tub-shaped recess to close it, the evaporator or the jacket of padding material applied thereto comes into contact with the tub base, the tub rims and the inner cover. It has been found to be advantageous for the inner cover to have no webs projecting into the evaporator accommodation space at least in the region of the evaporator, but to be fastened lying flat on the rims of the tub-shaped recess. Sealing beads of padding material, in particular foam beads, can be provided for sealing at the rims of the inner cover and/or at the rims of the tub-shaped recess so that no clicking noises can arise between the inner cover and the inner wall of the tank either.
The invention will be explained in more detail in the following with respect to a preferred embodiment and to associated drawings. There are shown in the drawings:
The refrigerator 1 shown in the Figures includes a substantially cubic cooling tank 2 which can be closed by a door 3. The inner space 4 of the cooling tank 2 shown in
The tub-shaped recess 6 is substantially rectangular, with the lower edge (cf.
The tub-shaped recess 6 can be closed by an inner cover 20 which is shown in
As
The evaporator 8 furthermore corresponds with respect to its thickness approximately to the depth of the tub-shaped recess 6 which would have to be measured perpendicular to the plane of the drawing in
As
If the evaporator 8 has the prescribed jacket 12 of soft, yielding padding material, the freezing state shown in
In contrast to this,
Number | Date | Country | Kind |
---|---|---|---|
10 2005 015 842.0 | Apr 2005 | DE | national |
20 2005 008 066.7 | May 2005 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP2006/002900 | 3/30/2006 | WO | 00 | 10/9/2007 |